Glossary Terms
Here is a list of terms that are being used when referencing anything to do with hair loss/hair transplant.
A
Alopecia: [Gk, alopex, fox (mange)], it can be partial or complete lack of hair
Alopecia Androgenetica: [Gk, alopex, fox (mange) + Gk, andros + genein, to produce], the medical term for male or female pattern baldness.
Alopecia Areata: [Gk, alopex, fox (mange) + L, area, open space], hair loss in sharply defined shapes
5 alpha-reductase: this enzyme is needed to change testosterone to dihydrotestosterone (DHT). Type 1 5-alpha reductase is found mainly in the skin and type 2 5-alpha reductase is found in the prostate.
Anagen: [Gk, ana, up, again + genein, to produce], the rising stage of hair, which shows big variation, ranging from two to six or more years.
Androgen: [Gk, andros + genein, to produce], a steroid hormone that can be found in men
Apoptosis: [Gk, apo, separation + ptosis, falling], automatic cell death.
Azelaic Acid: a physically occurring saturated dicarboxylic acid with the substance name of 1, 7-heptanedicarboxylic acid and a molecular mass of 188.22. Azelaic acid is a nutritional part of whole grain cereals and animal products.
B
Biopsy: [Gk, bios, life + opsis, view], the elimination of a small part of living tissue from an organ or other part of the body for microscopic test.
C
Catagen: [Gk, kata, down, under + genein, to produce], the small transition stage of the hair growth phase, lasting two to three weeks.
Clone: [Gk, klon, a plant cutting], a collection of genetically matching cells or organisms resulting from a particular common cell.
Crown: [L, corona, an encircling structure], the superior part of an organ or arrangement, such as the top of the head.
Cuticle: The external shell of hair, composed of overlapping scales made of neutral keratin protein. It gives hair gleam and shine and also provides some of its force.
D
Dermal Papilla: The dermal papilla is located at the bottom of the hair follicle. The dermal papilla contains nerves and blood vessels, which provide glucose for energy and amino acids to make keratin. This arrangement is enormously significant in the regulation of hair growth since it has receptors for both androgens and hair-promoting units.
Dermatology: [Gk, derma, skin + logos, science], the study of the skin, together with the anatomy, physiology, and pathology of the skin and the analysis and management of skin disorders.
Dermis: [Gk, derma, skin], the coating of the skin, just below the epidermis, consisting of papillary and reticular layers and containing blood and lymphatic vessels, nerves and nerve endings, glands and hair follicle units.
DHT: short term for dihydrotestosterone. Classified as a ‘sex hormone’, there is no well delineated connection to the levels of DHT and libido or sexual activity. Other than causing hair growth on the face and upper pubis (but having just the contrary outcome on the scalp), the role of DHT in the adult human male is not yet known.
Donor Area: region of the scalp (usually along the sides) where hair is extracted from to be transplanted to the scarred area.
Dutasteride: a medicine currently under growth by GlaxoSmithKline, which is a double inhibitor of the 5-alpha reductase enzymes in charge for converting testosterone to DHT.
E
Effluvium: [L, effluvium, a flowing out], a steady flow, which may pertain to unexpected hair shedding.
Epidermis: [Gk, epi, on or upon + derma, skin], the superficial, avascular, layers of the skin, made up of an outer, dead cornified part and a deeper, living, cellular part. All in all, the layers are between 0.5 to 1.1 mm.
Etiology: [Gk, aitia, cause + logos, science], the origin of a disease.
F
Finasteride: the general name for Propecia and Proscar, which are drugs that bind with the type 2 5-alpha reductase enzyme and decrease the quantity of DHT in the prostate and serum.
Follicle: [L, folliculus, small bag], a pouch like depression, such as the hair follicles within the dermis that enclose the hair roots.
Frontal Hairline: [L, frons, forehead], the separation of vellus to terminal or transitional hair in and adjacent to the midline of the frontal part of the head.
G
Generic: [L, genus, kind], of or pertaining to a substance, product, or medicine that is not protected by trademark; the same in substance composition but not essentially equal in remedial result.
Glycerin or Glycerine: [Gk, glykeros, sweet], a sugary, neutral, oily liquid that is a pharmacologic grade of glycerol. Glycerin is used as a moistening instrument for chapped skin, as an element of suppositories for constipation and as a sweetening instrument and vehicle for drug preparations.
H
Hamilton-Norwood: a graphic scale representing the amount of hair loss / recession of alopecia androgenetica in men.
Hirsutism: [L, hirsutus, hairy], extreme body or facial hair as an outcome of heredity, hormonal dysfunction, porphyria or prescription.
Hormone: [Gk, hormaein, to set in motion], a compound chemical substance formed in one part or organ of the body that initiates or regulates the movement of an organ or a group of cells in another part of the body.
Hypertrichosis: extreme hair growth over and above the normal for the age, sex and race of a person, in distinction to hirsutism, which is excess hair growth in women following a male distribution pattern. Hypertrichosis can expand all over the body or can be isolated to small patches.
Hypothyroidism: (underactive thyroid gland) is the word used to describe a state in which there is a compact level of thyroid hormone (thyroxine) in the body. This can cause various symptoms, including: tiredness, weight gain, constipation, aches, dry skin, lifeless hair/hair loss and feeling cold.
I
Infundibulum: is the cup or funnel in which a hair follicle grows, also The better, or uppermost portion, of the hair follicle.
Intermediate Hair: transitional scalp hairs are around 1 cm in length. They require the surface of terminal hair, but have much more thickness and body than vellus hair.
In Vitro: [L, in, within + vitreous, glassware], of a biologic effect happening in laboratory device.
In Vivo: [L, in, within + vivo, alive], of a biologic effect occurrence in an alive organism.
Isthmus: is the shortened section of the hair follicle, extending from the connection of the erector pili muscle (bulge region) into the entry of the sebaceous gland duct.
K
Keratin: [Gk, keras, horn], a fibrous, sulfur-containing protein that is the main part of the epidermis, hair, nails and enamel of the teeth.
Ketoconazole: an antifungal prescription that inhibits biosynthesis of ergosterols or other sterols.
L
Ludwig Staging: a representation of the severity of alopecia androgenetica in women
Lunago: [L, down], the spongy, fine hair that covers much of the foetus starts in the fifth month and is usually shed before birth.
M
Micrograft: [Gk, micros, small] means grafts with 1 or 2 hairs, mini grafts are those with 3 or 4 hairs, and a megasession is a process in which more than 1000 micrografts and minigrafts are inserted in a single session.
Midline: area towards the center of the scalp.
Miniaturisation: The critical process by which dihydrotestosterone (DHT) shrinks hair follicles; a key indicator of androgenetic alopecia.
Minoxidil: a piperidinopyrimidine derivative vasodilator that possesses hair growth stimulant properties, probably involving direct stimulus of hair follicle epithelial expansion. The first FDA drug approved for the treatment of MPB.
O
Occiput: [L, occiput, atlas], the back part of the head.
Oestrogen: [Gk, oistros, gadfly + genein, to produce], one of a group of hormonal steroid compounds that support the growth of female secondary sex characteristics.
P
Papilla: The tiny root area at the base of hair, which receives the nutrients needed for hair growth.
Pharmacodynamics: [Gk, pharmakon, drug + dynamis, power], the study of how a drug acts on a living creature.
Posterior Scalp: The region at the back of the head.
Pilosebaceous Unit: [L, pilus, hair + sebum, fat], of or pertaining to a hair follicle unit and its oil gland.
Proprietary: [L, proprietas, a property], of or pertaining to a result, such as a drug or device, that is made for income.
Propylene Glycol: a colourless thick liquid used as a solvent in the preparation of definite medications. It also inhibits the development of fungi and microbes.
R
Receptor Site: [L, recipere, to receive +situs, location], a position on a cell exterior where certain molecules, such as enzymes, neurotransmitters, or viruses, attach to interrelate with cellular mechanism.
Recession: [L, recedere, to retreat], a weakening.
Recipient Site: The bald area where the extracted hairs (usually from the donor area) are transplanted to.
Retin-A: the proprietary name for a preparation of retinoic acid, used in the management of acne and sun damage to the skin
Retinoic Acid (also tretinoin, isotretinoin or all-trans-retinoic acid): the cis-trans form of vitamin A. Retinoids cause a mild chemical peel on the skin and are very significant to all epithelial structure.
S
Scleroderma: [Gk, skliro, hard, derma, skin], a constant hardening and reduction of the skin and connective tissue throughout the body. It can cause hair loss over the affected areas.
Sebaceous: [L, sebum, sweat], greasy, oily, typically referring to the oil-secreting glands of the skin or to their secretion.
Sebum: [L, grease], the greasy emission of the sebaceous glands of the skin, composed of keratin, fat and cellular debris.
Steroid: [Gk, stereos,solid + eidos, form], any of a large number of hormonal substances with a comparable essential chemical configuration, formed mostly in the adrenal cortex and gonads.
Superoxide Dismutase (SOD): chemicals that catalyses the destruction of oxygen free radicals. It protects oxygen metabolizing cells against the damaging effects of superoxide free radicals.
Suture: Stich.
T
Telogen: [Gk, telos, end + genein, to produce], the latent stage of the hair growth cycle lasting for about 100 days.
Temples or Temporal Areas: [L, tempus, temple], the lateral-frontal regions of the head.
Terminal Hair: [L, terminus, boundary] of or pertaining to the thicker hair on the scalp that are modulated and contain a growth stage of many years.
Testosterone: a naturally occurring androgenic hormone.
Theory of Donor Dominance: logical basis for hair transplantation stating that hair’s genetic code resides inside the hair follicle and not in the receiver site into which it is transplanted.
Trichotillomania: [Gk, trikhos, hair, tillein, pull out (hair)] an irrational desire to pull out one’s hair.
V
Vellus: the spongy, fine hair casing all parts of the body except palms, soles and areas where other types of hair are usually found. True vellus hairs have no erector pili muscle, but have huge sebaceous glands. Vellus scalp hairs attain lengths less than 1 cm.
Vertex: [L, vertex, summit], the top of the head towards the posterior piece, together with the area or areas at which the hair grows in a coiled model.